Retrobiosynthetic nuclear magnetic resonance analysis of amino acid biosynthesis and intermediary metabolism. Metabolic flux in developing maize kernels.
نویسندگان
چکیده
Information on metabolic networks could provide the basis for the design of targets for metabolic engineering. To study metabolic flux in cereals, developing maize (Zea mays) kernels were grown in sterile culture on medium containing [U-(13)C(6)]glucose or [1,2-(13)C(2)]acetate. After growth, amino acids, lipids, and sitosterol were isolated from kernels as well as from the cobs, and their (13)C isotopomer compositions were determined by quantitative nuclear magnetic resonance spectroscopy. The highly specific labeling patterns were used to analyze the metabolic pathways leading to amino acids and the triterpene on a quantitative basis. The data show that serine is generated from phosphoglycerate, as well as from glycine. Lysine is formed entirely via the diaminopimelate pathway and sitosterol is synthesized entirely via the mevalonate route. The labeling data of amino acids and sitosterol were used to reconstruct the labeling patterns of key metabolic intermediates (e.g. acetyl-coenzyme A, pyruvate, phosphoenolpyruvate, erythrose 4-phosphate, and Rib 5-phosphate) that revealed quantitative information about carbon flux in the intermediary metabolism of developing maize kernels. Exogenous acetate served as an efficient precursor of sitosterol, as well as of amino acids of the aspartate and glutamate family; in comparison, metabolites formed in the plastidic compartments showed low acetate incorporation.
منابع مشابه
Breakthrough Technologies Retrobiosynthetic Nuclear Magnetic Resonance Analysis of Amino Acid Biosynthesis and Intermediary Metabolism. Metabolic Flux in Developing Maize Kernels
Information on metabolic networks could provide the basis for the design of targets for metabolic engineering. To study metabolic flux in cereals, developing maize (Zea mays) kernels were grown in sterile culture on medium containing [U-C6]glucose or [1,2C2]acetate. After growth, amino acids, lipids, and sitosterol were isolated from kernels as well as from the cobs, and their C isotopomer comp...
متن کاملStarch biosynthesis and intermediary metabolism in maize kernels. Quantitative analysis of metabolite flux by nuclear magnetic resonance.
The seeds of cereals represent an important sink for metabolites during the accumulation of storage products, and seeds are an essential component of human and animal nutrition. Understanding the metabolic interconversions (networks) underpinning storage product formation could provide the foundation for effective metabolic engineering of these primary nutritional sources. In this paper, we des...
متن کاملImpacts of seed priming with salicylic acid and sodium hydrosulfide on possible metabolic pathway of two amino acids in maize plant under lead stress
Heavy metals pollution is one of the key environmental problems. In this research, the effect of seed priming with salicylic acid and sodium hydrosulfide was investigated on methionine and arginine amino acids contents and some compounds derived from their metabolism as well as ZmACS6 and ZmSAMD transcripts levels in maize plants under lead stress. For this purpose, maize seeds were soaked in s...
متن کاملMetabolomics analysis of the saliva in patients with chronic hepatitis B using nuclear magnetic resonance: a pilot study
Objective(s): Hepatitis B virus infection causes chronic disease such as cirrhosis and hepatocellular carcinoma. The metabolomics investigations have been demonstrated to be related to pathophysiologic mechanisms in many disorders such as hepatitis B infection. The aim of this study was to investigate the saliva metabolic profile of patients with chronic hepatitis B in...
متن کاملMetabolic-flux profiling of the yeasts Saccharomyces cerevisiae and Pichia stipitis.
The so far largely uncharacterized central carbon metabolism of the yeast Pichia stipitis was explored in batch and glucose-limited chemostat cultures using metabolic-flux ratio analysis by nuclear magnetic resonance. The concomitantly characterized network of active metabolic pathways was compared to those identified in Saccharomyces cerevisiae, which led to the following conclusions. (i) Ther...
متن کاملذخیره در منابع من
با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید
برای دانلود متن کامل این مقاله و بیش از 32 میلیون مقاله دیگر ابتدا ثبت نام کنید
ثبت ناماگر عضو سایت هستید لطفا وارد حساب کاربری خود شوید
ورودعنوان ژورنال:
- Plant physiology
دوره 125 3 شماره
صفحات -
تاریخ انتشار 2001